We'll move all terms to the left
side:
2^2x - 6^(x+1) + 5*3^2x =
0
We'll write 6^x = 2^x*3^x, also 6^(x+1) =
(6^x)*6
6^(x+1) =
6*2^x*3^x
We'll re-write the
equation:
2^2x - 6*2^x*3^x + 5*3^2x =
0
We'll divide by
3^2x:
(2/3)^2x - 6*(2/3)^x + 5 =
0
We'll substitute (2/3)^x =
t
t^2 - 6t + 5 = 0
We'll apply
quadratic formula:
t1 = [6 +
sqrt(36-20)]/2
t1 = (6+4)/2
t1
= 5
t2 = (6-4)/2
t2 =
1
We'll substitute (2/3)^x = 1, where 1 =
(2/3)^0
(2/3)^x = (2/3)^0 <=> x =
0
(2/3)^x = 5 <=> x*ln (2/3) = ln
5
x = ln
5/ln(2/3)
The values of x that represent the
solutions of the equation are: x = 0 and x = (ln
5)/ln(2/3).
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